* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
  background-color: #f5f7fa;
  color: #333;
  line-height: 1.6;
}

.container {
  width: 90%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 15px;
}

.hidden {
  display: none !important;
}

/* 头部样式 */
.header {
  background-color: #2c3e50;
  color: white;
  padding: 15px 0;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo i {
  font-size: 28px;
}

.logo h1 {
  font-size: 22px;
  font-weight: 600;
}

/* 主内容区域 */
.main {
  padding: 30px 0;
}

/* 英雄区域 */
.hero {
  text-align: center;
  padding: 40px 0;
  margin-bottom: 30px;
}

.hero h2 {
  font-size: 32px;
  color: #2c3e50;
  margin-bottom: 15px;
}

.hero p {
  font-size: 18px;
  color: #7f8c8d;
  max-width: 600px;
  margin: 0 auto;
}

/* 上传区域 */
.upload-section {
  margin-bottom: 40px;
}

.upload-area {
  background: white;
  border-radius: 12px;
  padding: 40px 20px;
  text-align: center;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
  border: 2px dashed #e0e6ed;
  transition: all 0.3s ease;
}

.upload-area:hover {
  border-color: #3498db;
  background-color: #f8fafc;
}

.upload-area i {
  font-size: 60px;
  color: #3498db;
  margin-bottom: 20px;
}

.upload-area h3 {
  font-size: 24px;
  margin-bottom: 10px;
  color: #2c3e50;
}

.upload-area p {
  color: #7f8c8d;
  margin-bottom: 25px;
}

.upload-btn {
  display: inline-block;
  background: #3498db;
  color: white;
  padding: 12px 30px;
  border-radius: 50px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 4px 10px rgba(52, 152, 219, 0.3);
}

.upload-btn:hover {
  background: #2980b9;
  transform: translateY(-2px);
  box-shadow: 0 6px 15px rgba(52, 152, 219, 0.4);
}

.upload-btn input {
  display: none;
}

/* 文件状态提示 */
.file-status {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 15px;
  padding: 10px 15px;
  background-color: #e8f5e9;
  border-radius: 8px;
  color: #2e7d32;
  border: 1px solid #c8e6c9;
  transition: all 0.3s ease;
}

.file-status i {
  font-size: 18px;
  color: #4caf50;
}

/* 开始生成按钮动画效果 */
.generate-btn.pulse {
  animation: pulse 1.5s infinite;
}

@keyframes pulse {
  0% {
    box-shadow: 0 0 0 0 rgba(46, 204, 113, 0.4);
  }
  70% {
    box-shadow: 0 0 0 10px rgba(46, 204, 113, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(46, 204, 113, 0);
  }
}

/* 文件选择后的上传区域样式 */
.upload-area.file-selected {
  border: 2px solid #2ecc71;
  box-shadow: 0 0 15px rgba(46, 204, 113, 0.2);
  transform: scale(1.01);
  transition: all 0.3s ease;
}

/* 进度条样式 */
.progress-card {
  background: white;
  border-radius: 12px;
  padding: 25px;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
}

.progress-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
}

.progress-header h3 {
  font-size: 20px;
  color: #2c3e50;
}

#progressPercentage {
  font-weight: 600;
  color: #3498db;
  font-size: 18px;
}

.progress-bar {
  height: 10px;
  background: #ecf0f1;
  border-radius: 5px;
  margin-bottom: 20px;
  overflow: hidden;
}

#progressBar {
  height: 100%;
  width: 0%;
  background: #3498db;
  border-radius: 5px;
  transition: width 0.5s ease;
}

.progress-message {
  display: flex;
  align-items: center;
  gap: 10px;
}

.progress-message i {
  color: #3498db;
}

.progress-message p {
  color: #7f8c8d;
}

/* 图谱区域 */
.graph-section {
  margin-bottom: 40px;
}

#graphContainer {
  background: white;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
}

.graph-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 25px;
  border-bottom: 1px solid #eee;
}

.graph-header h3 {
  font-size: 20px;
  color: #2c3e50;
}

.graph-controls {
  display: flex;
  gap: 15px;
}

.search-box {
  position: relative;
}

.search-box i {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  color: #95a5a6;
}

.search-box input {
  padding: 10px 15px 10px 35px;
  border: 1px solid #e0e6ed;
  border-radius: 50px;
  width: 250px;
  font-size: 14px;
}

#refreshGraph {
  background: transparent;
  border: none;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: #7f8c8d;
  font-size: 18px;
  transition: all 0.3s ease;
}

#refreshGraph:hover {
  background: #f8f9fa;
  color: #3498db;
}

#networkContainer {
  height: 500px;
  background: #f8fafc;
}

.graph-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 15px 25px;
  border-top: 1px solid #eee;
}

.legend {
  display: flex;
  gap: 20px;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
}

.color {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  display: inline-block;
}

.color.mastered {
  background: #2ecc71; /* 已掌握 - 绿色 */
  box-shadow: 0 0 10px rgba(46, 204, 113, 0.5);
}

.color.partial {
  background: #f39c12; /* 部分掌握 - 橙色 */
  box-shadow: 0 0 10px rgba(243, 156, 18, 0.5);
}

.color.unmastered {
  background: #e74c3c; /* 未掌握 - 红色 */
  box-shadow: 0 0 10px rgba(231, 76, 60, 0.5);
}

.stats {
  font-size: 14px;
  color: #7f8c8d;
}

/* 节点状态动画效果 */
.node-pulse {
  animation: nodePulse 2s infinite;
}

@keyframes nodePulse {
  0% {
    transform: scale(1);
  }
  50% {
    transform: scale(1.05);
  }
  100% {
    transform: scale(1);
  }
}

/* 测试区域 */
.quiz-section {
  margin-bottom: 40px;
}

#quizContainer {
  background: white;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
}

.quiz-header {
  padding: 20px 25px;
  border-bottom: 1px solid #eee;
}

.quiz-header h3 {
  font-size: 20px;
  color: #2c3e50;
  margin-bottom: 5px;
}

.quiz-header p {
  color: #7f8c8d;
}

.quiz-body {
  padding: 25px;
  display: flex;
  flex-direction: column;
}

/* 对话历史样式 */
.chat-history {
  background: white;
  border-radius: 12px;
  padding: 20px;
  margin-bottom: 20px;
  max-height: 400px;
  overflow-y: auto;
  box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

.chat-history-message {
  margin-bottom: 20px;
  padding: 15px;
  border-radius: 8px;
  background: #fff;
  box-shadow: 0 2px 5px rgba(0,0,0,0.05);
  position: relative;
}

.question-message {
  border-left: 4px solid #3498db;
}

.answer-message {
  border-left: 4px solid #2ecc71;
}

.feedback-message {
  border-left: 4px solid #f39c12;
}

.question-message .question-header {
  display: flex;
  align-items: center;
  margin-bottom: 10px;
}

.question-message .question-header i {
  margin-right: 10px;
  color: #3498db;
}

.answer-message .answer-header {
  display: flex;
  align-items: center;
  margin-bottom: 10px;
}

.answer-message .answer-header i {
  margin-right: 10px;
  color: #2ecc71;
}

.feedback-message .feedback-header {
  display: flex;
  align-items: center;
  margin-bottom: 10px;
}

.feedback-message .feedback-header i {
  margin-right: 10px;
}

.feedback-message .feedback-header i.success {
  color: #2ecc71;
}

.feedback-message .feedback-header i.error {
  color: #e74c3c;
}

.question-content, .answer-content, .feedback-content {
  padding-left: 5px;
}

.question-card {
  background: white;
  border-radius: 12px;
  padding: 20px;
  margin-bottom: 20px;
  box-shadow: 0 5px 15px rgba(0,0,0,0.05);
}

.question-header {
  display: flex;
  align-items: center;
  margin-bottom: 15px;
}

.question-header h4 {
  margin: 0;
  font-size: 18px;
  color: #2c3e50;
}

.question-header i {
  margin-right: 10px;
  font-size: 20px;
  color: #3498db;
}

.answer-area {
  margin-top: 20px;
}

.answer-area h4 {
  font-size: 16px;
  margin-bottom: 10px;
  color: #7f8c8d;
}

#userAnswer {
  width: 100%;
  height: 120px;
  padding: 15px;
  border: 1px solid #e0e6ed;
  border-radius: 8px;
  font-size: 16px;
  resize: vertical;
  transition: border-color 0.3s;
}

#userAnswer:focus {
  outline: none;
  border-color: #3498db;
  box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.1);
}

.feedback-card {
  background: white;
  border-radius: 12px;
  padding: 25px;
  box-shadow: 0 5px 15px rgba(0,0,0,0.05);
}

.feedback-header {
  display: flex;
  align-items: center;
  margin-bottom: 15px;
  padding-bottom: 10px;
  border-bottom: 1px solid #eee;
}

.feedback-header h4 {
  margin: 0;
  font-size: 18px;
  color: #2c3e50;
}

.feedback-header i {
  margin-right: 10px;
  font-size: 24px;
}

.feedback-body {
  line-height: 1.6;
}

#submitAnswer, #nextQuestion {
  display: block;
  width: 100%;
  background: #3498db;
  color: white;
  border: none;
  padding: 14px;
  border-radius: 8px;
  font-size: 16px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.3s ease;
  margin-top: 20px;
}

#submitAnswer:hover, #nextQuestion:hover {
  background: #2980b9;
  transform: translateY(-2px);
  box-shadow: 0 4px 10px rgba(52, 152, 219, 0.3);
}

#noQuestion {
  text-align: center;
  padding: 40px 20px;
}

#noQuestion i {
  font-size: 60px;
  color: #bdc3c7;
  margin-bottom: 20px;
}

#noQuestion h4 {
  font-size: 22px;
  color: #2c3e50;
  margin-bottom: 10px;
}

#noQuestion p {
  color: #7f8c8d;
}

/* 添加反馈区域样式 */
.feedback-body p {
  margin: 10px 0;
  line-height: 1.6;
}

.success-text {
  color: #2ecc71;
  font-weight: bold;
  margin-top: 15px;
}

.error-text {
  color: #e74c3c;
  font-weight: bold;
}

.countdown {
  font-style: italic;
  color: #7f8c8d;
  margin-top: 10px;
}

/* 问题生成提示样式 */
#questionGenerating {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 10000;
  display: none;
}

.question-generating-notification {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 15px;
  background-color: rgba(52, 152, 219, 0.1);
  border-radius: 8px;
  margin-bottom: 20px;
  animation: fadeIn 0.3s ease;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.question-generating-notification i {
  font-size: 24px;
  animation: spin 1s linear infinite;
}

.success {
  color: #2ecc71;
}

.error {
  color: #e74c3c;
}

.chat-section {
  padding: 40px 0;
  background-color: #f7f9fc;
}

.chat-box {
  border: 1px solid #ccc;
  border-radius: 10px;
  padding: 20px;
  background: white;
}

.chat-history {
  max-height: 300px;
  overflow-y: auto;
  padding-bottom: 20px;
}

.chat-input {
  display: flex;
  gap: 10px;
  margin-top: 10px;
}

#qaInput {
  flex: 1;
  padding: 10px;
  height: 80px;
  resize: none;
  border-radius: 6px;
  border: 1px solid #ccc;
}

#qaSubmitBtn {
  padding: 10px 20px;
  background: #357edd;
  color: white;
  border: none;
  border-radius: 6px;
  cursor: pointer;
}

#qaSubmitBtn:hover {
  background: #285ec7;
}

.msg {
  margin: 10px 0;
  line-height: 1.6;
}

.user-msg {
  text-align: right;
  color: #2c3e50;
}

.ai-msg {
  text-align: left;
  color: #1e8449;
}

.error-msg {
  color: #c0392b;
}

.chat-feedback ul {
  padding-left: 20px;
  margin-top: 10px;
}

.chat-feedback li {
  margin-bottom: 6px;
}


/* 页脚样式 */
.footer {
  background: #2c3e50;
  color: #ecf0f1;
  padding: 20px 0;
  text-align: center;
  margin-top: 40px;
}

.footer p {
  font-size: 14px;
}

.context-modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.5);
  display: none; 
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.context-modal.show {
  display: flex; 
  opacity: 1;
}

/* 节点操作模态框 - 固定居中显示 */
#nodeActionModal {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 300px;
  background: white;
  border-radius: 8px;
  padding: 20px;
  box-shadow: 0 5px 15px rgba(0,0,0,0.3);
  z-index: 10000;
  display: none;
  opacity: 0;
  transition: opacity 0.3s ease, transform 0.3s ease;
}

#nodeActionModal.show {
  display: block;
  opacity: 1;
  transform: translate(-50%, -50%) scale(1);
}

/* 模态框出现时的缩放动画 */
@keyframes modalAppear {
  from {
    transform: translate(-50%, -50%) scale(0.9);
    opacity: 0;
  }
  to {
    transform: translate(-50%, -50%) scale(1);
    opacity: 1;
  }
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-bottom: 10px;
  border-bottom: 1px solid #eee;
}

.modal-title {
  margin: 0;
  font-size: 1.2rem;
  font-weight: 600;
  color: #2c3e50;
}

.close-modal {
  font-size: 1.5rem;
  font-weight: bold;
  cursor: pointer;
  background: none;
  border: none;
  color: #7f8c8d;
  transition: color 0.3s;
}

.close-modal:hover {
  color: #333;
}

.modal-body {
  padding: 15px 0;
}

.modal-body p {
  margin-bottom: 15px;
  color: #555;
  line-height: 1.5;
}

.action-buttons {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 15px;
}

.action-btn {
  padding: 10px;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 5px;
  font-size: 0.9rem;
  background-color: #3498db;
  color: white;
  transition: background-color 0.3s, transform 0.2s;
  box-shadow: 0 2px 5px rgba(52, 152, 219, 0.2);
}

.action-btn:hover {
  background-color: #2980b9;
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(52, 152, 219, 0.3);
}

.action-btn i {
  margin-right: 5px;
}

/* 节点详情模态框 */
.node-modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10000;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.node-modal.active {
  opacity: 1;
}

.modal-content {
  background-color: white;
  padding: 20px;
  border-radius: 8px;
  width: 80%;
  max-width: 500px;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
  position: relative;
  animation: modalFadeIn 0.3s ease;
}

@keyframes modalFadeIn {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* 加载动画样式 */
@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

.loading-spinner {
  display: inline-block;
  width: 18px;
  height: 18px;
  border: 2px solid #f3f3f3;
  border-top: 2px solid #3498db;
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin-right: 8px;
  vertical-align: middle;
}



/* 新增导航栏样式 */
.header-nav {
  display: flex;
  gap: 20px;
  margin-left: auto;
}

.header-nav ul {
  display: flex;
  list-style: none;
  gap: 20px;
}

.header-nav a {
  color: white;
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  padding: 5px 10px;
  border-radius: 4px;
  transition: background-color 0.3s;
}

.header-nav a:hover {
  background-color: rgba(255, 255, 255, 0.1);
}

/* 英雄区域功能卡片样式 */
.hero-features {
  display: flex;
  justify-content: center;
  gap: 30px;
  margin-top: 30px;
  flex-wrap: wrap;
}

.feature-card {
  background: white;
  border-radius: 12px;
  padding: 25px;
  text-align: center;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
  flex: 1 1 280px;
  max-width: 320px;
  transition: transform 0.3s, box-shadow 0.3s;
}

.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
}

.feature-card i {
  font-size: 36px;
  color: #3498db;
  margin-bottom: 15px;
}

.feature-card h3 {
  font-size: 18px;
  margin-bottom: 10px;
  color: #2c3e50;
}

/* 功能区域样式 */
.features-section {
  margin-bottom: 60px;
  background: white;
  border-radius: 12px;
  padding: 40px 20px;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
}

.section-title {
  font-size: 28px;
  text-align: center;
  margin-bottom: 40px;
  color: #2c3e50;
  position: relative;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -15px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  background: #3498db;
  border-radius: 3px;
}

.section-desc {
  text-align: center;
  max-width: 600px;
  margin: 0 auto 30px;
  color: #7f8c8d;
  font-size: 16px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 30px;
}

.feature-item {
  background: white;
  border-radius: 12px;
  padding: 30px;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
  border: 1px solid #eee;
  transition: transform 0.3s, box-shadow 0.3s;
}

.feature-item:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
  border-color: #3498db;
}

.feature-icon {
  text-align: center;
  margin-bottom: 20px;
}

.feature-icon i {
  font-size: 48px;
  color: #3498db;
}

.feature-item h3 {
  font-size: 20px;
  margin-bottom: 15px;
  color: #2c3e50;
  text-align: center;
}

.feature-list {
  list-style: none;
  margin-top: 15px;
}

.feature-list li {
  margin-bottom: 8px;
  color: #7f8c8d;
  position: relative;
  padding-left: 20px;
}

.feature-list li::before {
  content: "•";
  position: absolute;
  left: 0;
  color: #3498db;
  font-weight: bold;
}

/* 工作原理部分样式 */
.working-principle {
  margin-bottom: 60px;
  background: white;
  border-radius: 12px;
  padding: 40px 20px;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
}

.workflow {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 20px;
}

.workstep {
  flex: 1 1 200px;
  max-width: 240px;
  text-align: center;
  background: white;
  border-radius: 12px;
  padding: 25px;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
  position: relative;
  border: 1px solid #eee;
}

.workstep:hover {
  border-color: #3498db;
}

.step-number {
  position: absolute;
  top: -15px;
  left: 50%;
  transform: translateX(-50%);
  width: 30px;
  height: 30px;
  background: #3498db;
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
  font-size: 14px;
}

.workstep i {
  font-size: 36px;
  color: #3498db;
  margin: 20px 0 15px;
}

.workstep h3 {
  font-size: 16px;
  margin-bottom: 10px;
  color: #2c3e50;
}

.workstep p {
  color: #7f8c8d;
  font-size: 14px;
}

/* 常见问题手风琴样式 */
.faq-section {
  margin-bottom: 60px;
  background: white;
  border-radius: 12px;
  padding: 40px 20px;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
}

.faq-accordion {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  margin-bottom: 15px;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.faq-question {
  background: #f8fafc;
  padding: 20px;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border: 1px solid #eee;
  transition: background-color 0.3s;
}

.faq-question:hover {
  background: #f1f8fe;
}

.faq-question h3 {
  font-size: 16px;
  color: #2c3e50;
  margin: 0;
  display: flex;
  align-items: center;
  gap: 10px;
}

.faq-question i {
  transition: transform 0.3s;
  color: #95a5a6;
}

.faq-answer {
  background: white;
  padding: 0;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.5s ease, padding 0.3s ease;
  border: 1px solid #eee;
  border-top: none;
}

.faq-answer p {
  padding: 20px;
  color: #7f8c8d;
  margin: 0;
}

.faq-item.active .faq-answer {
  max-height: 500px;
  padding: 20px;
}

.faq-item.active .faq-question i {
  transform: rotate(180deg);
}

/* 页脚增强样式 */
.footer {
  background: #2c3e50;
  color: #ecf0f1;
  padding: 40px 0 20px;
  margin-top: 60px;
  text-align: left;
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 30px;
  margin-bottom: 30px;
}

.footer-info h3 {
  font-size: 20px;
  margin-bottom: 15px;
  color: white;
}

.footer-info p {
  color: #bdc3c7;
  margin-bottom: 20px;
}

.social-links {
  display: flex;
  gap: 15px;
}

.social-links a {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  transition: background-color 0.3s;
}

.social-links a:hover {
  background: #3498db;
}

.footer-links h4 {
  font-size: 16px;
  margin-bottom: 15px;
  color: white;
  position: relative;
  padding-bottom: 10px;
}

.footer-links h4::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 40px;
  height: 2px;
  background: #3498db;
}

.footer-links ul {
  list-style: none;
}

.footer-links li {
  margin-bottom: 10px;
}

.footer-links a {
  color: #bdc3c7;
  text-decoration: none;
  transition: color 0.3s;
}

.footer-links a:hover {
  color: #3498db;
}

/* 新增的UI元素通用样式 */
.upload-tips, .input-tip, .btn-tooltip, .search-tip {
  font-size: 13px;
  color: #7f8c8d;
  display: block;
  margin-top: 5px;
  text-align: center;
}

.btn-tooltip {
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(0, 0, 0, 0.7);
  color: white;
  padding: 5px 10px;
  border-radius: 4px;
  white-space: nowrap;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s, visibility 0.3s;
}

.generate-btn:hover .btn-tooltip, .action-btn:hover .btn-tooltip {
  opacity: 1;
  visibility: visible;
}

/* 图谱控制区域样式 */
.graph-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 15px;
}

.graph-stats {
  font-size: 14px;
  color: #7f8c8d;
}

.filter-group, .view-switch {
  display: flex;
  align-items: center;
  gap: 10px;
}

.filter-btn, .view-btn {
  background: #f8fafc;
  border: 1px solid #e0e6ed;
  padding: 8px 15px;
  border-radius: 50px;
  cursor: pointer;
  font-size: 13px;
  transition: all 0.3s;
}

.filter-btn:hover, .view-btn:hover {
  background: #eef2f7;
  border-color: #c0ccda;
}

.filter-btn.active, .view-btn.active {
  background: #3498db;
  color: white;
  border-color: #3498db;
}

/* 测试区域增强样式 */
.quiz-meta {
  display: flex;
  gap: 20px;
  font-size: 14px;
  color: #7f8c8d;
}

.chat-history {
  max-height: 300px;
  overflow-y: auto;
}

.history-empty {
  text-align: center;
  padding: 20px;
  color: #95a5a6;
}

.history-list {
  list-style: none;
}

.history-item {
  margin-bottom: 15px;
  padding: 15px;
  border-radius: 8px;
  background: #f9f9f9;
}

.history-question {
  border-left: 4px solid #3498db;
}

.history-answer {
  border-left: 4px solid #2ecc71;
}

.history-feedback {
  border-left: 4px solid #f39c12;
}

.history-item h5 {
  margin-bottom: 5px;
  font-size: 15px;
  color: #2c3e50;
}

.history-item p {
  color: #7f8c8d;
  margin: 0;
}

.question-hint {
  background: #f0f7ff;
  padding: 10px;
  border-radius: 6px;
  margin-top: 10px;
  display: none;
}

.answer-tips {
  font-size: 13px;
  color: #7f8c8d;
  margin-top: 5px;
}

.feedback-explanation {
  margin-top: 15px;
  padding-top: 15px;
  border-top: 1px solid #eee;
}

.feedback-explanation h5 {
  color: #2c3e50;
  margin-bottom: 10px;
}

.feedback-actions {
  display: flex;
  gap: 10px;
  margin-top: 20px;
}

.hint-text {
  font-size: 14px;
  color: #95a5a6;
  margin-top: 10px;
}

/* 响应式设计调整 */
@media (max-width: 768px) {
  .header {
    padding: 15px 0;
  }
  
  .logo {
    flex-direction: column;
    align-items: flex-start;
    gap: 5px;
  }
  
  .header-nav {
    margin-top: 15px;
    width: 100%;
    justify-content: center;
  }
  
  .hero-features, .feature-grid, .workflow {
    gap: 20px;
  }
  
  .feature-card, .feature-item, .workstep {
    flex: 1 1 100%;
  }
  
  .graph-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 15px;
  }
  
  .graph-controls {
    flex-wrap: wrap;
    justify-content: flex-start;
  }
  
  .filter-group, .view-switch {
    margin-bottom: 10px;
  }
  
  .quiz-meta {
    flex-direction: column;
    gap: 10px;
  }
  
  .feedback-actions {
    flex-direction: column;
    gap: 10px;
  }
}
